Picture frame



FIG. 1 is a front elevational view of a picture frame showing our new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a right side elevational view thereof; and

FIG. 4 is a sectional view taken along line 4--4 _of FIG. 1 

The ornamental design for a picture frame, substantially as shown. 